Laboratory experiments on Alfvén waves caused by rapidly expanding plasmas and their relationship to space phenomena

Physics – Plasma Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

15

Space Plasma Physics: Laboratory Studies, Solar Physics, Astrophysics, And Astronomy: Coronal Mass Ejections, Space Plasma Physics: Waves And Instabilities, Interplanetary Physics: Ejecta, Driver Gases, And Magnetic Clouds, And Astronomy: Magnetic Fields

Scientific paper

There are many situations which naturally occur in space (coronal mass ejections, supernovas) or are man-made (upper atmospheric detonations) in which a dense plasma expands into a background magnetized plasma that can support Alfvén waves. The Large Plasma Device (LAPD) at UCLA is a machine in which Alfvén wave propagation in homogeneous and inhomogeneous plasmas has been studied. A new class of experiments which involve the expansion of a dense (initially n laser-produced/n background >> 1) laser-produced plasma into an ambient highly magnetized plasma capable of supporting Alfvén waves will be presented. The 150 MW laser is pulsed at the same 1 Hz repetition rate as the plasma in a highly reproducible experiment. The laser beam impacts a solid target such that the initial plasma burst is directed across the ambient magnetic field. The interaction results in the production of intense shear and compressional Alfvén waves, as well as large density perturbations. The waves propagate away from the target and are observed to become plasma column resonances. The magnetic fields of the waves are measured with a 3-axis inductive probe. Spatial patterns of the magnetic fields associated with the waves and density perturbations are acquired at over 10,000 spatial locations and as a function of time. Measurements are used to estimate the coupling efficiency of the laser energy and kinetic energy of the dense plasma into wave energy. The shear wave generation mechanism is due to field-aligned return currents, which replace fast electrons escaping the initial blast.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Laboratory experiments on Alfvén waves caused by rapidly expanding plasmas and their relationship to space phenomena does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Laboratory experiments on Alfvén waves caused by rapidly expanding plasmas and their relationship to space phenomena, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Laboratory experiments on Alfvén waves caused by rapidly expanding plasmas and their relationship to space phenomena will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1147891

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.